W123 OM648 Project - Page 2 - PeachParts Mercedes-Benz Forum

Won24 · #16 02-21-2022, 06:16 AM

I'm thinking about doing this same thing with my w124 for the same reason. OM606 is too expensive, and if be happy with just the factory 648 power (although I'm sure I'd end up with a little more power. I was looking at using Baldur's ECU the DID1 as it comes with a base map, although black smoke's may as well.

Let me know if you need anything 3D printed, not sure what that would be but I'm happy to help out. If you're nearby (I'm in SoCal) I'd be happy to lend a hand too!

BirthdayBenz · #17 02-21-2022, 07:16 AM

Quote:

Originally Posted by w123fanman

I'm considering an OM647 for a W123, seems to be closer to the spirit of a 300D. Was your weight with oil in the engine and trans?

Either way, very interested in how this turns out. I will pick up a 612 harness for this build.

The OM648 engine with all accessories and oil was 555lbs. With the 722.6 attached the whole thing was 745lbs. I've not yet attached the flywheel, adapter plate and BMW transmission. I plan to post weight differences between the OM617, 4speed, 722.6, OM648 and BMW trans at some point after I have the OM648/BMW trans assembly together.

BirthdayBenz · #18 02-21-2022, 07:26 AM

Quote:

Originally Posted by Won24

I'm thinking about doing this same thing with my w124 for the same reason. OM606 is too expensive, and if be happy with just the factory 648 power (although I'm sure I'd end up with a little more power. I was looking at using Baldur's ECU the DID1 as it comes with a base map, although black smoke's may as well.

Let me know if you need anything 3D printed, not sure what that would be but I'm happy to help out. If you're nearby (I'm in SoCal) I'd be happy to lend a hand too!

The blacksmoke ecu comes with a complete tune. Not sure if I'll need to data log and work with them remotely once its installed to workout any issues. It's a stock ecu from an OM613 that has had an updated map and a bunch of things EGR things turned off.

I'm in South Carolina, I'll definitely shoot you a PM if I find something I need printed!

BirthdayBenz · #19 02-21-2022, 07:37 AM

My Parts from sendcutsend arrived. Looks like I designed them correctly as all the holes line up!

I need to clean the inside of the intake and tap the holes for the swirl flaps that I removed and plug them with bolts. Then the intake can go back on along with the OM613 engine harness.

BirthdayBenz · #20 02-25-2022, 06:26 AM

Not much progress to show in the past few days. Just cleaning things. Cleaning nasty EGR gunk... scrubbing, brushing using the steam machine and making a mess. Scraping the oil pan gasket which is the most stubborn gasket I've ever encountered. I soak it in WD40 every so often then scrape a little soak it repeat...

I tapped the swirl flap holes to M12x1.5 and then realized I only had M12X.1.75 bolts around so I proceeded to order bolts.

At least having ordered bolts they're all uniform. I had a bunch of copper crush rings around from oil changes as I never remove the drain plug. I have an oil extractor. Glad I kept them around.

More cleaning for now and waiting on gaskets from Mercedes.

BirthdayBenz · #21 03-01-2022, 02:39 PM

Looks like the OM606 oil pump does not fit on the OM648 block.

606 has a square outlet where as the 648 has a round one with rubber gasket. Looks like I'll be looking for another pump.

wschotty · #22 03-02-2022, 11:06 PM

Nice project!

Check out post 58 on this thread for some others who have been down this road:

OM606 rear sump oil pan?

BirthdayBenz · #23 03-03-2022, 08:17 AM

Quote:

Originally Posted by wschotty

Nice project!

Check out post 58 on this thread for some others who have been down this road:

OM606 rear sump oil pan?

Thanks! I think I found that post when scouring the internet but didn't thoroughly read it. Having read it now looks like they just used the o-ring even through square vs round mating surfaces exists. Makes me fell more comfortable about doing that, which was my plan.

BirthdayBenz · #24 03-03-2022, 02:22 PM

Another unforeseen issue....

The bolts from the OM648 pump (right) are too short to work with the OM606 pump. I was able to find bolts from my old M113 oil pump (left) which appear to be the correct length.

BirthdayBenz · #25 03-08-2022, 09:49 AM

I installed the pump and windage tray this morning. Two of the main bearing cap bolts needed to be swapped to allow the windage tray to bolt on. That extra 90 degrees post torque always stress me out.

Then when trying to mount the pan I've ran into a larger issue. The OM606 pan doesn't clear the OM648 flywheel.

The OM606 flywheel must be a smaller diameter. I think I'm going to find a machine shop who will cut 1/2in off the back of the pan so it clears the flywheel. I think finding an OM606 flywheel and then figuring out the starter situation plus crank position trigger for the ECU will be more problematic than just cutting the pan. I have the large adapter plate for the manual transmission so I'm not worried those two bottom bell housing bolts.

BirthdayBenz · #26 03-09-2022, 06:52 AM

I went to the closest machine shop and they weren't comfortable cutting the pan so I just did it myself by hand with a hacksaw like a maniac.

Now I can take this thing off the stand and work towards fitting the transmission and adapter plate.

mike280 · #27 03-09-2022, 09:33 AM

Thanks for posting this up. Keep up the good work the 648 is a great engine

BirthdayBenz · #28 03-19-2022, 08:16 AM

I've been planning and running new electrical things.

I ran the positive battery cable salvaged from the W211 from the trunk. I ended up doing this twice. First I went up over the rear fender following the vacuum lines but then when I made it to the firewall I wasn't happy with the length. I removed the cable and re routed it by drilling a hole next to the passenger side strut. It now routes around the fuel tank and I've got an extra 2ft or so of cable to work with.

Bonus! I found an old mouse nest behind the fuel tank and vacuumed that out.

I used the power distribution block from the W211. Mounting it in the passenger kick panel. I've still got some reinforcement/better mounting to do as the angels in the W123 floor area are not the same as the W211. Nothing is fully bolted down in the final position in any of these photos.

The red cable on the distribution block is wired to the W123 main power wires that were originally directly connected to the battery. This will provide power to all the original systems in the vehicle.

Engine side of firewall

ECU Mounting:
The ECU will be mounted on the old battery tray. I found and modified a waterproof camera case.

Engine photo for no reason. That turbo looks large...

I ordered the wrong throwout bearing and wrong clutch alignment tool. So I need to find the correct ones and reorder. This is why the engine is still on the stand and not assembled to the transmission.

BirthdayBenz · #29 03-23-2022, 08:09 AM

I had mounted the adapter plate and flywheel but I'm experiencing some clearance issues between the automatic flywheel portion and adapter plate.

Looking good:

But the adapter plate contacts the automatic flywheel ever so slightly.

The new flywheel bolts on top of the automatic flywheel in order to retain use of the crank position sensor pickup and ring gear.

I had not removed the automatic flywheel when first installing the new manual flywheel and adapter plate, but ended up doing so while troubleshooting the clearance issue. What I found between the automatic flywheel and crank was a spacer.

I removed that spacer and reinstalled the flywheel and have just the right amount of clearance between the flywheel and adapter plate. I still however heard metal to metal contact when rotating the assembly. Again, everything came apart and this time I found some witness marks on the OM606 oil pan.

I'm out of time this morning but I think if I remove some material from the witness mark area on the OM606 oil pan everything will fit.

I reached out to DiselpumpUK to verify the installation procedure as I have no documentation. I'm just interested in confirming if the spacer is typically removed.

BirthdayBenz · #30 03-25-2022, 06:49 AM

Removed some material from the OM606 oil pan. Flywheel on and off about 3 times to get it just right. Everything is assembled and torqued no rubbing.

Hopefully the correct BMW parts for the transmission will arrive today. Those would be TOB, Clutch fork, retainer spring, and clutch fork pivot mount. I'm camping this weekend so wont be able to do any more work until next week.